I've essentially the same issue, but with Kanger SubTank coils. My first TC mod was a Pioneer 4 You ipv4, and it has "worked" well for me, but it is just too bulky and cheaply made, plus the screen too difficult to read. So, I also purchased a Joyetech eVic-VT, and that's where the issue began. The eVic-VT would read the coil, Ni200 - 0.15, correctly (most of the time) and a vaping I would go. But, if I set the mod down for 10 - 15 minutes when I came back to it vapor production had dropped significantly. Checking the settings when that happened I saw that the eVic-VT now was reading the coil at 0.12 or 0.13. Soon I learned how to puff a time or two at this lower reading, unscrew the tank at the 510, and when I screwed it immediately back on the eVic-VT would read it at 0.15 - 0.17. I would then lock the Ohms on the VT and return to good vapor production and vaping. However, again, setting the mod down for 10 - 15 the whole scenario would happen again (wash, rinse, repeat). It seems, unlike the ipv4 (upon which my Kanger tanks and Ni coils work just fine), that the eVic-VT Ohms lock was useless, or hard wired to a much lower percentage than the default 25% range of our DNA200s. So, I returned the eVic-VT under warranty but the replacement did the same thing. In speaking with my online retail rep., he told me that the eVic-VT works much better with Ti coils, so I purchased a Joyetech ONE Mega tank and a five pack of Ti - 0.4 coils. Nothing changed; I experienced the same issue with the Ti as I had with the Ni. As information: I run the ipv4 at 30 Joules, 410 F, with the Ohms locked at 0.15 (for Ni200), and I tried to use the same settings on the eVic-VT (watts instead of Joules). Well, the eVic-VT soon became a paperweight and I stuck with vaping the ipv4. That was until over the holidays when I dropped it (ahhhgain). As I was on travel, I located the nearest B&Mâthank goodness for smartphonesâand decided to purchase a Wismec Reuleaux RX200 (the only DNA200 they had was the Volcano LavaBox at $120 more). I was back at the B&M the next day exchanging the RX200 for the LavaBox, as the RX200 acted much the same way as the eVic-VT. During the exchange, I also purchased a new package of five Kanger OCC Ni200 - 0.15 coils, and certified them online as authentic. (I had packed two extra Kanger Ni200 - 0.15 coils, bringing them with me from home, and the RX200 blew both of them at first install. "Sizzle - pop," said the first coil, and I thought, "Oh, a bad coil." "Sizzle - pop," said the second coil, and I thought, "Oh, this RX200 is another potential paperweight.") Now, I'm having similar experience with my two DNA200s (I purchased a Reuleaux DNA200 online after I returned home). At first I tried using the same trick as with the eVic-VT: taking a puff, unscrewing the tank just to screw it back on to get a higher Ohms reading, and then Ohms locking the higher reading. Now though, I've decided to change my settings to 50 watts, 500 F, and no Ohms lock; I let the board read and adjust to whatever resistance it sees. As I write this, I'm vaping my LavaBox (50 watts, 500 F, no lock) and it is reading a three day old, authenticated Kanger Ni200 - 0.15 coil, installed in a new, authenticated Kanger SubTank (which I connected at room temp.) as having 0.23 Ohms resistance. While vapor production at these settings is great, the vapor is just a little too warm for my tastes. But, if I lower the temperature setting vapor production suffers. Hopefully soon I'll find that happy medium... BRB... My tank went dry and I had to go refill it. The LavaBox now is reading 0.22 Ohms for the refilled tank. This is perfect! Good vapor production and not too warm. But, hold on, now I'm getting a "Weak Battery" warning. LOL! I never would have thought stopping smoking, which I did two years ago (and with an original Joyetech eVic no less), would be this complicated; difficult yes, but this complicated?
